Adjustable-pitch propeller



LT. F-REDEmCK.

ADJUSTABLE FITCH PROPELLER.

APPLICATION FILE-D MAY l5. 1919.

Patented N ov. 28

LASR-099 V\ WITNESSES:

Patented Nov. 28,l 1922.

uNrraD STATES PATENT OFFICE;

' LOUIS T.FBEDERICK, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO `WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION F PENNSYL- vAmA.

Application led May. 15,

To all whom t may concern Beit known that I, Louis T. FREDERICK, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of- Pennsylvania,

able-Pitch Propellers, in is a specification. l yinvention relates to propellers and of which the follow- ',lt-)lmore particularly to propellers of the adwas provided with Adiametrically disposed,

vtubular, blade-receiving arms in which the e inner ends of wooden propeller blades were secured for turning movement, and means wasmounted upon the hub, or Within the same, for turning or tilting theblades to lvary their 'pitchfand to held the blades in adjusted position.

One object'v of my invention consists in providing sleeves whichv may be mounted` for turning movement within the arms of a hub and which may be actuated by the usual l blade-tilting mec blades ofcomposite material. l

A still further object of my Ainvention resides in the provision of means for molding theblades in the sleeves'so as 'to securely anchor them thereto. Y

With these and other objects `in view, .my invention will be more fully described, illustrated in the drawings, in the several views of which corresponding numerals indicate like parts, and then particularly pointed out-inl the claims. Fig. 1 is a rear elevation-of improved propeller; Fig. 2 is partly in section; Fig. '3 vis a rear elevation part of my l of the hub portion, partly in section, and

Flg. 4 is an end view of the hub, partly in section. Y A

`My! propeller comprises a hub-f1 formed with diametrically disposed tubular arms the inner ends of the propeller lblades 4.

The outer endof each arm 2 is internally I `beveled to form a seat` and externally threaded, as bestshown in Fig. 2.' Each sleeve 3 s have invented a". new and useful Improvement in Adjust-v anism ,and which are. 30 adapted to Vhold the inner ends of molded a plan` view,

2 to receive sleeves 3 1n which are secured l ADJUSTABLE-FITCH PROPELLER.

1919. serial No. 297,353.

' formed, at its inner end, to it'snugly within the inner portion of its receiving arm 2 for. .free turning movement and, 'near its outer end, With an annular shoulder 5one face of which is beveled to engage thev seat of the arm and the opposite faceof which receives a bearing race 6 having bearing balls 7. A locking ring 8 isA threaded about tho end of each arm and has a flange l9 which engages the vrace 6, Whereby the race is held in .place and the sleeve A3 is secured within the arm for free turning movement.

The `blades 4 of my improved propeller may preferably be formed of fibrous material .and a suitable binder, such as a phenolic condensation product', which has been hardenedby the application of heat and pressure.

jF or 'example,-a blade may comprise superimposed layers of fibrous sheet material, such aspaper or duck. impregnated With a binder,'such as a phenolic condensation product.` The impregnated sheets may be assembled in the manner disclosed in a copending application A,filed by 1918, Serial N o. 268,954, (Case No. 6283) or in the manner disclosed in a copending application filed by D. A. Dickey, Dec. 30, 1918, Serial ,No. 268,949, (Case No. 6187) and assigned to the Westinghouse Electric & Manufacturing Company. 1 The assembled blade may ythen be disposed in a mold of any suitable character and cured by subject- 111g it to heat and pressure to compact and shape it and toharden the binder.

Preferably the inner endsl of the bladesl are formed with a tapered socket 10 for the sake of lightness and are molded directly into the sleeves 3. vIf such is the case, wedge rings 11 are forced into the inner ends of the blades during-'the molding operation to expand such ends and fonce them into engagement with the :flaring inner ends of the sleeves so as to securely lock the 'blades to thesleeves. If desired, the inner faces of the sleeves and the outer faces of the `me Dec. 30, I

wedge rings may be roughened to more securely engage the molded material of the Y blades.

Slidably mounted upon the rear end of the hub 1 is a shifting collar 12 which is keyed or votherwise secured to the hub to vturn therewith. The shifting collar includes an inner prtion which turns with e the hub andan outer portion 13 lwhich is I connected to the inner portion-by a bearing race 14x so that it may remain stationary While the Ahub and inner portion revolve.

vAny suitable control lever or link (not shown) may be connected to the outer pory tion 13a-so that, while thepropeller is in finner ends of the sleeves and propeller,

e ing flight.

operatiom the shifting collar may be 'reciprocated upon the hub. Pivotally connected to the inner member ofthe collar are4 blade tilting `levers l5 which pass through slots 16 formed in the arms of the hub and through alined openings in the blades, a's best shown inFigs. 2 and 4.

As the blade-shifting mechanism forms no .part of my invention, a more ldetailed description is `deemed to be -f unnecessary.

fective and economical means of construct-- ing a propeller of/ the variable-pitch type in Which the. blades may be of a molded composition, such asa fibrous material and a hardened binder. It will also be clear thatby molding the blades'A directly into the hub-engagingsleeves, absolute securing of theblades to the hub in insured.

Obviously, various` changesv in construction may be resorted to and, for this reason, no limitations' are tov be imposed upon in theclaims.` l

y invention other than those "set forth claim as my invention: l. An adjustable-pitch propeller comprising a hub having radial tubular arms, tapered-sleeves rotatably mounted on the arms,I means for adjustably turning the blades, the inner ends of which are molded linto the sleeves.

3. An adjustable-.pitch propeller comprisving blades of fibrous material and a heathardened binder, tapered sleeves into which the inner ends of the blades are molded, and a'hub adapted to receive the sleeves.

Ll. In an adjustable-pitch propeller,a sleeve internally flared at one end, a propeller blade of ibrousmaterial and a hardened binder having its inner end disposed within the sleeve and molded therein, and means molded into such end of the blade for eX- panding it in the flared portion of the sleeve. y

.5. In an adjustable-pitch propeller, a sleeve internally iare'd at one end, a propeller blade of fibrous mat-erialand a hardened, binder having its inner end disposed within the sleeve, such end of the blade being formed with a recess, and a Wedging member forced into the recess to expand the adjacent portion of the blade into theflared portion of the sleeve.

vIn testimony whereof, I have hereunto subscribed my name this 30th day of April LOUIS T. FREDERICK. 

